Description:

Significant ecosystem services derive from the coastal wetlands of the Laurentian Great Lakes even though they have undergone substantial declines since European settlement. Basin-wide, two-thirds of the original coastal wetlands have been lost, and the remaining 126,000 ha of US coastal wetlands and =70,000 ha of Canadian wetlands are assaulted by water level controls, diking, chemical contamination, sedimentation, nutrient enrichment, invasive species, and watershed disturbance. Nonetheless, some wetlands of the upper Great Lakes are in near-pristine condition and even degraded wetlands provide some services. Existing information suggests that wildlife habitat, fisheries support, and water quality are significant ecosystem services provided by Great Lakes coastal wetlands. 30 species of waterfowl, 155 breeding bird species, and 55 species of reptiles and amphibians are supported by coastal wetland habitats across the Basin. Nearly all of the sport and commercially-important Great Lakes fish species use coastal wetlands for life-cycle functions, and Great Lakes food webs are supported by the export of thousands of young sport and forage fish per coastal wetland per year. Indices of biological integrity based upon bird, amphibian, and fish assemblages indicate declines in community condition, and presumably declines in the wildlife and fishery services, with watershed disturbance across the Basin. Preliminary estimates of the water quality service of coastal wetlands suggest a Basin-wide retention of 3,897 mg P and 52,830 mg N per year. Estimates of carbon sequestration suggest that less than 90 g C yr-1 are retained across the Basin. The plant crops ecosystem service is limited to wild rice production and is not commercially important for these systems. Storm surge protection may be locally important where fringing wetland remain. Reliable estimates of nutrient, sediment, and carbon retention are lacking. To support management decisions, quantitative relationships between specific stressors or land use practices and the delivery of ecosystem services are needed, as are ecosystem service indicators.